1. Field of the Invention
The present invention relates to an abnormality diagnostic device for a battery pack adapted to detect if there is a break in an electrical connection between a cell and a detection terminal provided between terminals of the cell.
2. Background Information
A battery pack generally has a plurality of cells and a plurality of detection terminals for detecting the voltages between the terminals of the cells. Japanese Laid-Open Patent Application Publication No. 2001-157367 discloses a device for determining if there is a break in an electrical connection between a detection terminal and a cell of such a battery pack. The conventional device controls switches to short circuit the detection terminals of the cell for a prescribed amount of time and then to cancel the short circuit. If, after a prescribed amount of time has elapsed, the voltage between the detection terminals remains substantially the same as when the detection terminals were short circuited, then the device determines that there is a break in the electrical connection between the cell and the detection terminals.
Japanese Laid-Open Patent Application Publication No. 2005-168118 discloses another device configured to alternately short-circuit connections between detection terminals of a plurality of cells, which form a battery pack, to determine if a cell is over-discharged or a break in a wire connection exists.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved abnormality diagnostic device. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.